As the shipwrecked but glamorous Jessica Lange approaches a towering, jungly island in the 1976 remake of King Kong, she murmurs silkily, ‘I feel this is going to be the biggest thing in my life. A pedantic viewer might add: ‘ And the wettest.’ The setting for her encounter with the giant ape was Kauai, a Hawaiian island whose central mountain is the rainiest place in the world.
The island is certainly dramatic enough to be the home of Hollywood’s most famous beast. An extinct volcano called Mount Waialeale – pronounced ‘why-alley-alley’ – rises from the ocean, its vast crater almost permanently covered in clouds. Knife-edge ridges separate deep ravines carved by millennia of rain, and luxuriant greenery tumbles down to golden beaches. Not surprisingly, Kauai is a popular location for filmmakers: part of the South Pacific was shot here, as were the opening sequences of Raiders of the Lost Ark.
Waialeale is one of a string of Volcanoes that rise from the ocean floor, 18,000ft (5500m) below. They were formed one by one as lava rose to the ocean floor from a ‘hot spot’ deep within the Earth. The ocean floor here is constantly moving north-westwards at about 4in (100mm) a year as one of the Earth’s plates glides over the semi-molten layer below. The hot spot, however, remains where it is.
Each volcano was gradually carried by the gliding crust away from its spring of the molten rock and become extinct, allowing another to form above the hot spot. Waialeale, the volcano on Kauai, began to be formed in this way nearly 6 million years ago, and Hawaii, the newest of the islands, is still forming.
Waialeale is well-named, for it means over-flowing water. The rain falling on its summit averages 486in (12,350mm) a year, almost 20 times that of London. This is the average figure – in 1948 the rainfall totalled almost a third as much again. This deluge of rain is dumped by moisture-laden winds that sweep across the Pacific Ocean from the northeast. As the air strikes Waialeale’s flanks, it howls up its ravines, condenses and releases its watery burden.
As a result of this vast amount of water is the mountains’ hot-house vegetation. The Alakai Swamp, a peaty depression on its flanks, sustains a jungle of rare plants and birds in a misty morass of tea-coloured waters and black mud bogs. Trees that loom like ghosts through Alakai’s mists include the lapalapa, whose leaves flutter in the slightest breeze, and the ohia, which bears bright red blooms. All trees are upholstered in sodden layers of moss, which turns finger-thin branches into green ‘sponges’ as thick as an arm.
Waialeale has few large animals. The only land mammal to arrive on the island with no human help was the bat; all others have been introduced by the succession of peoples who have come to live in this subtropical paradise. Polynesians arrived here in about AD 750, after a journey across 2400 miles (4000km) of the ocean in double-hulled canoes. In the 19th century, Japanese, Americans, Filipinos, Chinese and Europeans from many countries came to Kauai, many of them drawn by the island’s sugar plantations.
The Polynesians brought pigs to the island, and today intrepid biologists forcing their way through waist-deep mud and down precipitous ravines encounter occasional wild pigs. Goats, introduced by the British navigator Captain Cook, who visited the island in 1778, also from the mountain sloped. Their hoovers get little support in the mud and soggy peat and have become splayed to the size of saucers.